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Hairy Solar Cells Could Mean Higher Efficiency
kitzilla writes "Two research groups working independently have come up with what they say are cheap processes for growing nanowires to be used with solar cells. The 'hairy' cells provide a direct path for electrons collected at the panel face to reach an electrode, something which has the potential to dramatically improve system efficiency."
If every solar cell advance that was announced actually led to improvements of solar cells you could actually buy, then they would be 99.9999999% efficient and cost less than crackers.
But I'm not bitter, nooooooo.
The problem is that a large portion of the lab performance-enhancing techniques are so insanely expensive that they *can't* go into production. Many of them - particularly exotic materials or multi-junction cells - are prohibitively expensive to make, given the meager performance improvements. I think Nanosolar has the right idea for now - craptastic cells made cheap. Who cares if they're large if they're incredibly inexpensive?
If I am not completely mistaken "classical" semi conductor cells can reach efficiencies of 40%, meaning that even with perfect 100% efficiency you would get at best a factor 2.5 improvement. Of course, 100% efficiency is an impossibility and thus I think we can safely assume that these cells will never reach more than 80%-90% efficiency, which would be an improvement of a factor of 2 over current technology. Now last estimate I saw was that in Europe solar cells work out to be about 4 times as expensive as wind power (which is itself rather pricey ), so even assuming the 100% efficiency, efficiency gains alone cannot make solar economical.
Add in to this that a large part of the cost of solar is the energy needed to produce the cells, which means that if you get that energy from a more expensive power source, the price of the cells will increase. I.e, if one started to replace relatively cheap generation capacity with more expensive solar cells, then the cost of energy, and hence the cost of the cells, would increase.
It would therefore appear to me that for solar to have a chance to become competitive what is needed is focus on lowering the cost of producing the cells, because the gains from improving their efficiency cannot offset their presently large price, and it appears unlikely that pushing for higher and higher efficiencies will be possible without making the cells more expensive.
AC's got it right. For those who are TLTRTFM (Too Lazy To ...), what the poster should have said is that they help channel charge carriers away from the junction so that they don't immediately recombine. *That* is one of the holy grails of PV design, and one of the reasons that current production cells are incredibly inefficient.
Thermal solar is the lowest costs of all AE except for hydro. At this time, it is the same costs as a recent coal plant i.e. a plant that is cleaner than average. Of course, the solar thermal is clean all the way around.
In addition, it is fairly easy to store the heat in salts and generate during the night. Spain, Arizona, New Mexico, Northern Africa, etc. are all headed in GW size of solar thermal. Spain expects to sell power back to its northern neighbors at a tidy profits. Arizona has a 1/4 GW install going in. In addition, another group is close to building a 1/2-3/4 GW in NM or southern CO (possible to take advantage of 3 different power companies and 5 states incentives).
All in all, the only joke is a fool like you.
Let us not become the evil that we deplore.
These guys are scammers ... it's the old When Hairy Met Sili Con.
The higher the technology, the sharper that two-edged sword.
Wake me up when there's actually a cheap product. These articles need their own icon; maybe Bigfoot, the Easter Bunny, Santa Claus, the Loch Ness Monster, or La Chupacabra.
I swear to God...I swear to God! That is NOT how you treat your human!
Hairyness makes everything better. I mean, just look at me...